The present invention concerns a magnetic head mounted on a floppy disk driver for reading, from recording to or erasing information from on a diskette.
The floppy diskette, used as a recording medium of a computer, is magnetized by the magnetic head to record information, the recorded informations is then read by the magnetic head.
Though the principle of recording and reading information using a magnetic head is the same with a conventional recording tape and its peripheral technologies the difference between the magnetic head for reading information from a diskette and the conventional sound recorder lies in the fact that the magnetic head has a high-density structure so that a great amount of information may be recorded on the diskette.
The conventional high-density magnetic head, as shown in FIG. 4, includes an erasing head section A and a recording/reading head section B arranged in parallel with a space between and a ceramic casing C enclosing the sections. The width of the erasing head section is slightly wider than that of the recording/reading head section B.
The two head sections A and B respectively have in their midsection a straight gap A', B' where a magnetic field is formed to record and read information, as is well known in the art.
The processing of information on a diskette with the conventional magnetic head will be described hereinafter. As shown in FIG. 5, if the track of the diskette is in the IBM basic format, and a gap B' of the recording/reading head section B is in a position where it does not correspond with the synchronizing signal SYNC of track, the searching of the diskette continues. After the gap B' is synchronized with the synchronizing signal SYNC, it moves to address mark A/M to sense it. After sensing the address mark A/M, the recording/reading head section B proceeds to record or read information, or the erasing head section A proceeds to erase information.
In this case, after the information recorded on the track of the diskette is erased to record new information, there remains, on the track of the diskette a non-erased portion D that corresponds to the space between the gap A' of the erasing heads section A and the gap B' of the recording/reading head section B, as shown in FIG. 6. This non-erased portion D causes interference when reading information on an adjacent track. Therefore, data errors occur so that compatibility with the IBM basic format is impossible.